Plug-in coil mounting



PLUG-IN COIL MOUNTING Filed May 5, 1964 2 Sheets-Sheet l I N VEN TOR.

Dec. 3, 1935. w. G. WHEAT 2,023,157

PLUG-IN COIL MOUNTING Filed May 3, 1934 2 Sheets-Sheet 2 INVENTOR.

Patented Dec. 3, 1935 UNITED STATES PATENT OFFICE 2,023,157 PLUG-IN COILMOUNTING William G. Wheat, Kansas City, Mo. Application May 3, 1934,Serial No. 723,680 1 Claim. 175356) My invention relates to improvementsin plugrigidly bolted to the panel by bolts or rivets mum-- in coilmountings used in radio communication; her 3 and number 4. A flangedbottom or base, and the objects of my invention are, first, to number 1,is fitted inside the shield can number provide a plug-in coil mountingof great accessi- 6 and is held in place by rivets number 8. The

bility thereby allowing a rapid change of coils, multi-pronged socketbase, number 9, is held in covering the different short wave bands, bythe position by the bracket number I0 which is seoperator; and second,to provide a shielded recurely fastened to the base, number 1, bybolting cess well within the front of the receiver panel or riveting. togive adequate coil shielding from other coils The socket base, number 9,has a projecting 10 operating at similar frequency as well as othersurface area, number II, composed of any type 10 surrounding equipment;and third, to provide of insulating material, disc-like in shape, overfor a metal top or shield on the plug-in coil for the outer edge ofwhich fits the dust sleeve, numthe purpose of excluding dust as well ascompletber I2, which is of some non-metallic substance ing the metallicshield surrounding the plug-in such as bakelite or fibre. The forwardend of the 0011. sleeve rests against the inner lip of the circular 15 Iattain these objects by the means illustrated panel aperture, number I3,and is held in alignin the accompanying figures, in which ment by theforward circular aperture in the Figure 1 is a front panel View of thecomplete metallic shield can, number 6. plug-in coil assembly. Asectional line is drawn The small openings shown at numbers I4, I5,through the assembly, marked L- I6, I1, I8, and I9, Figure 4, are forthe passage 20 Figure 2 is a top view of the plug-in coil mountof thenecessary connecting cables to the socket ing assembly showing theshield cover rigidly atbase. tached to the panel 22 and the plug-incoil, A section of the plug-in coil with its metallic shown as Figure 5,inserted in position within pull handle and metallic shield cover andnon- 25 the shield through the circular aperture I3, in metallic dustcover is removed to show the as- 25 panel 22, Figure 3. sembly of atrimmer condenser, number 20, Fig- Figure 3 is a sectional view of theplug-in coil ure 5. Any material for the plug-in coil form mountingassembly taken along the section line may be used, such as bakelite,isolanite, etc. T0 of LL of Figure 1. give additional protection againstthe collection Figure 4 shows a rear view of the plug-in coil of dust ormechanical. damage to the winding 30 mounting. of the coil anon-metallic sleeve, number 2|, Figure 5 shows a side view of theplug-in coil. Figure 5, may be placed v i n in he Number I, Figure l, isa small aperture beneath full length of the coil.

the coil pull handle, number 2, for the purpose It is a well known factthat the old method of of adjusting the trimmer or band spreadconmounting the plug-1n coil inside the radio re-as merals or coloredmarkings on the coil top or bolted to the operating table, was, in manycases, 40

age are shown at number 5, Figure 1. was not conducive to long life ofthe tubes and The metallic shield mounting number 6, Figure other parts.3, is cylindrical in shape, having one end straight, To replace thecoils it was necessary to do so 15 the other end being flanged inward atright anby touch alone as the interior of the cabinet was gles and theopening therein being equal to the usually dark and the holes in thesocket base outside diameter of the dust sleeve number I2, could not beseen. It was at about this stage that Figure 3. This is done for thepurpose of securthe crowning mishap usually occurred. The head ing thedust shield in position at the front or phones,if'not well balanced onthe operators head 0 panel end of the shield. The said opening in theslid off into the receiver thereby causing damage end of the shieldbeing slightly larger than the if they struck any of the equipmenttherein. circular aperture through the panel face so as However, theworst feature of the old type of into allow the dust shield to slidethrough the shield terior coil mounting was the loss of time inmakopening and butt up against the inside of front ing the coil change.

5 panel number 22. The shield can assembly is In the panel mounted typeof coil this is not true for with the simple insertion of a fingerthrough the coil pull ring and the placing of a thumb against the panelface the coil comes out quickly. It is easy to replace for the aperturein the panel is about on a level with the operators eyes, and aftermeshing the contact points a slight push engages the coil.

While I have shown and described what I consider the preferredembodiment of the invention, I desire to have it understood that I donot limit myself in this connection, and that such changes may beresorted to, when desired, as fall within the scope of what is claimed.

What is claimed is:

In combination, a panel having an aperture therein, a metallic shieldcan rigidly attached to the rearward side of the panel opposite aperturewithin said panel, a dust shield secured between rear side of panelaperture and rear portion of shield can structure, a coil movablethrough said panel, said assembly including a coil form, a non-metallicclose fitting dust cover rigidly secured over the coil form, a variablecondenser mounted in the upper end of said coil form and having anadjusting screw, 10 and a metallic shield end cover for the coilassembly apertured opposite the adjusting screw of the condenser.

WILLIAM G. WHEAT.

assembly re- 5

